[elhigh]

An air dam, belly pan and lowering all are aimed at improving how the air behaves under the car, and of them I think the air dam is the cheapest and most convenient. We've seen effective air dams constructed out of plain old cardboard.

NOTE: Donkey CRX's two older Civics are running dams put together from Home Depot's Auto Body department. The white car appears to be wearing lawn edging and it looks surprisingly good, whereas the red car is equipped with a snow plow of an air dam from a big sheet of polyethylene. And both of those cars are consistently in the tippy-top of the MPG leaderboard. I don't remember if the cars are lowered, I think one of them is but it's a modest drop.